Controlled-Release Ferts Gain Stature

This landscape was fertilized with Spread it & Forget it, an enhanced-efficiency fertilizer (EEF). EEFs are manufactured using a patented process that encapsulates nutrients within special polymer coatings, and they release their nutrients gradually and evenly over an extended period of time, reducing runoff issues.PHOTO COURTESY OF AGRIUM ADVANCED TECHNOLOGIES.

Led by environmental activists, public sentiment against commercial fertilization is gaining momentum. As a result, many states are moving to enact legislation that restricts or prohibits fertilizer applications.

This past April, legislators in Maryland approved laws that affect numerous aspects of turf and ornamental fertilization, including product usage, ingredients, labeling and more. Earlier this year, New Jersey ratified a bill that will take effect in 2012, and is being closely observed by activists in nearby states who want to push for similar legislation, which its proponents describe as the most comprehensive fertilizer bill in the U.S.

In Florida, there’s intense disagreement about who has the legal authority to impose fertilizer bans or restrictions. Dozens of individual counties and municipalities across the state have crafted their own laws to determine how, when and where fertilizers may be used. The Florida legislature, however, is considering statewide regulations, rather than allowing each local jurisdiction to make its own rules. Other state governments do not allow a hodgepodge of city or regional ordinances.

On the other hand, many people around Florida believe that broad-based, statewide laws can’t address their unique local concerns and specific regional challenges. In fact, some counties are pushing to get “emergency” anti-fertilizer laws onto their books before the state rules take effect.

“It’s all very complicated, and I don’t see it getting any less complicated in the near future,” said Dr. Alan Blaylock, Ph. D., manager of agronomy at Agrium Advanced Technologies. “Policy-makers are reacting to the fears of their constituents and interest groups with what seems like a logical solution. But, part of the problem is these responses are often made without an understanding of the science of nutrient management and its consequences.”

Runoff the problem

The crux of the issue is fertilizer runoff, which can often be traced to improper application.

Unused plant nutrients may migrate through the soil for several reasons; once that happens, they’re considered pollutants. Water and gravity naturally deposit those escaped fertilizer elements in nearby ponds, lakes and streams, contributing to eutrophication. Eutrophication occurs when excess nitrogen and phosphorus get into the water, and nourish the aquatic plants and other organisms there, especially algae.

In some cases, algal blooms are formed, creating patches of discolored water covered with floating algae. Those can understandably call attention to the issue and stir public concern.

“When people see algal blooms in their neighborhood pond or local body of water, they call their homeowners’ association and want something done to clean it up,” said Blaylock. “That gets various agencies and interest groups involved, and it can become a political battleground.”

Identifying the causes

Many people feel that a rise in eutrophication and algal blooms can be attributed to a cumulative effect of both “point” and “nonpoint” polluting sources. A point source refers to a single polluter, such as a factory or a mine; nonpoint sources are widespread and individually unidentifiable.

In the case of fertilizer misuse and runoff, there may literally be millions of nonpoint contributors across the country. Fingers are specifically being pointed at the improper use of fertilizers by homeowners and other nonprofessional applicators.

State and local laws regulating fertilizer usage are evidence of concern about the potential for fertilizer misuse among nonprofessionals, and many of the new restrictions are based on common-sense considerations. For example, some laws prohibit fertilizers from being applied on frozen ground, near pavement or right before heavy rain; other laws require a fertilizer-free buffer zone between landscapes and water sources, such as streams or canals. Some states have “blackout” periods when fertilizers can’t be applied at all.

“The legislative efforts are usually focused on homeowners and lawn care operators,” said Dr. Eric Miltner, Ph.D., who spent 13 years at Washington State University and was involved with Washington’s new fertilizer laws. “Some homeowners have different priorities. They might just throw down a bag of fertilizer without really thinking about it, and a lot of them believe that if some fertilizer is good, then more is even better.”

However, many industry professionals are exempt from certain fertilizer laws in their respective states. Legislation often makes exceptions for golf courses, sports/municipal facilities, agricultural uses and qualified landscape situations, frequently with a stipulation that the users have been trained and certified in the proper handling and application of fertilizers.

Technology is the key

The dangers and repercussions of fertilizer misuse exist on different levels, some of which can’t be fixed with rules. For one thing, many of the laws are essentially unenforceable. If a homeowner is going to over-apply fertilizer, either intentionally or accidentally, what can be done to prevent it?

“That’s definitely part of the problem,” agreed Miltner. “A colleague of mine in the WSDA [Washington State Department of Agriculture] admitted they don’t have the resources to actively police the laws. That’s why manufacturers, blenders, retailers and university extension services are realizing it’s up to us to get people to comply.”

One step forward is the increased recognition of enhanced-efficiency fertilizers (EEFs) as useful tools, particularly slow-release or controlled-release products. The Association of American Plant Food Control Officials (AAPFCO) defines EEFs as fertilizers that increase nutrient availability/uptake and decrease losses to the environment when compared to appropriate traditional fertilizers.

EEFs are manufactured using a patented process that encapsulates nitrogen or other nutrients within special polymer coatings. When applied, the coated granules release their nutrients gradually and evenly over an extended period of time.

The opposite is true with traditional soluble fertilizers that dissolve into the soil quickly. When plants can’t readily absorb those nutrients, the potential significantly increases for them to be lost from the soil, sometimes into surface water and groundwater.

“Nitrogen in the soil is very mobile, which is important for plants to be able to rapidly take up what they need,” says Blaylock. “Healthy roots are aggressive feeders. Actively growing turfgrass consumes nutrients quickly, so the trick is to synch the nutrient supply to the plant demand. That’s exactly what slow and controlled-release fertilizers do. When you feed grass steadily and constantly, as the roots need it, the fertilizer doesn’t have a chance to get lost.”

By gradually delivering nitrogen and other nutrients to correspond to plants’ uptake, slow and controlled-release fertilizers can virtually eliminate the risk of nutrient loss. Better yet, that steady feeding minimizes surge growth and reduces the number of fertilizer applications needed during a season.

The New Jersey laws require a minimum of 20 percent slow-release nitrogen content in lawn fertilizers. In Florida, many counties have passed ordinances that mandate 50 percent of the nitrogen in a fertilizer be slow-release. In Maryland, fertilizer professionals are being encouraged to use EEFs voluntarily.

“It is imperative that legislators understand what the lawn and landscape industry is doing on its own, and what tools we currently use to reduce nitrogen runoff.” said Ken Mays, president of Scientific Plant Services, Inc., Baltimore, Md.

Doing things right

Fertilizer advocates and industry leaders have adopted “4R Nutrient Stewardship,” a science-based approach to best management practices. The system calls for the right product to be applied at the right rate, right time and right place.

“Proper use of plant nutrients can actually improve water quality, while banning them could have the opposite effect,” said Blaylock. “Properly fertilized plants are healthier, so they’re better able to utilize the nutrients in the soil and protect the soil resource from degradation. Unhealthy plants have poor root systems and stimulate less biological activity in the soil; they don’t use the nutrients they get efficiently, which leads to greater probability of nutrient and soil loss.”

“The advances in technology right now are amazing in terms of what we can do to control fertilizer release and minimize pollution,” says Miltner. “It’s exciting to realize we have the knowledge and abilities to do this right.”

Alan Whitney is marketing services manager for Agrium Advanced Technologies, and is based out of Loveland, Colo.